In a FinFET process, a gate oxide layer is disposed between a fin layer and a dummy poly layer, and a spacer is formed above and perpendicular to the gate oxide layer. However, in a succeeding process that etches the gate oxide, a leakage path to an epitaxy layer formed beside the fin layer may be introduced under the spacer. As a result, electron movement of a gate formed within the gate profile may be harmed by the leakage path.